One way to figure out what's appropriate for your site is to take a field guide and find wild places nearby that are roughly similar in sun exposure and soil/moisture and see what's growing there. Go in spring to see what's in bloom then. If you identify something that you like, see if there is a local supplier (see link for lists of NJ native plant suppliers).

I know there are plenty of native plants in my area that like sun and bloom in spring, and I would imagine the same is true for your area.

By the way, I think you've made a great start to your teaching garden - lucky kids!

- wd

Here is a link that might be useful: New Jersey Native Plant Society

This is a list for Georgia, but it might help you get some ideas and some of these would be native to NJ as well.

Do research their growing conditions (sun, shade, wet, dry, etc.) before deciding.

Here is a link that might be useful: Spring blooming list

I suggest Wild Columbine - Aquilegia canadensis. This is in full bloom here in central PA right now, and has had flowers for several weeks. Easily grown from seed and among the easiest natives to find in nurseries. If you leave some space unmulched at the base of the columbines, you'll have to pull some weeds but should also get lots of volunteer columbine seedlings next year which can be moved around the garden.

Also try violets. They bloom even earlier than columbine, depending on the species, and there are many species to choose. The showiest is Birdsfoot Violet, which is a relatively common plant in the native nursery business. The widespread Common Blue violet is also nice and very easy to find - you probably have some in the lawn. There are numerous other species, and you might find one or two growing in a spot with similar soil and sunlight as your garden and move a few. Around here Viola finriatula is common in dry, sunny spots and very showy in early spring. The big drawback to violets is their stature - they are low growers and can get lost in a garden if larger plants or weeds overtop them, and since they're small they can be hard to mulch properly. I would plant them in small areas that are easy to locate - at the base of a sign, for example - so that you will know where they are in the fall when you return for class even if weeds have grown over them. Violets do fine in full sun or shade.

ladyslppr....I like the idea of columbine, as well as the violets, but considering I mulch heavily, it might not be the best thing for me.

I mulch heavy and the columbine and violets do just fine.

I was thinking about other spring bloomers and I was realizing most of them are shady lovers...but here are a few suggestions that will do fine in the sun:

Shooting stars (dodecatheon meadia)
Wild Geranium (geranium maculatum)
Golden Alexanders (zizia aurea)
Prairie Trillium (Trillium recurvatum)

Another spring flower is Golden Ragwort, or one of the other, similar ragworts. Golden Ragwort has golden daisy-like flowers in May, and otherwise is a low-growing plant that likes moist to average soil.

According to the Plant Native web site, the following four wildflowers are all New Jersey natives that like sun and bloom in the spring:

Alumroot (Heuchera americana)
Blue Star (Amsonia montana)
Blue Wild Indigo (Baptisia australis)
Coreopsis lanceolata (Lanceleaf tickseed)